In recent years there has been much publicity and endorsement for a class of weapons generally known as smart weapons systems. These new weapons present a real potential for countering the numerical advantages of an enemy by utilizing advanced technological weapons which require little human intervention.
The smart weapons systems generally employ autonomous operations, e.g., missiles or submissiles, including an infrared, radar, or optical sensor, for scanning the targeted area of the missile or submissiles, and a data processor for analyzing the data acquired by the sensor and for directing appropriate munitions at specific targets. The data processor commonly includes digital circuitry for processing the data to identify and to select from surrounding background clutter one or more patterns or “signatures” corresponding to targets. In such smart weapons systems, each munition included therein is launched from a carrier, e.g., a main missile, helicopter, airplane, etc., which brings one or more of the munitions to a certain point with respect to the targets. In current systems, following launch from the carrier each of the munitions individually and independently searches for a target, acquires a target, and directs itself toward its acquired target.
The high cost of the carrier, especially when the carrier is a missile or a manned platform, has made it necessary to deliver a multitude of munitions over a target array for each carrier launched in order for the smart weapons system to be cost effective.
The carrier, whether it is a missile or an airplane, has specific payload limits including a specific volume available for storage of the munitions. When the munitions are submissiles, it is necessary that each of the submissiles be relatively small in diameter in order that they all fit within the carrier missile. Such constraint on the size of the submissiles necessarily restricts the amount of explosives carried thereby as well as the size of the sensor included in each submissile.
With regard to this last consideration, it is known that for any given wavelength, whether it be in the infrared or microwave spectrums, the basic quality of the data that a sensor is capable of acquiring is related to the square of the aperture size of the sensor. The ability to detect and to identify a target having a certain signature and located in a certain clutter environment, e.g., shrubs, rocks, trees, etc., is related to the resolution by which the target can be scanned by the sensor. For example, a 20 inch aperture microwave sensor will output data with a resolution 25 times better than a 4 inch aperture sensor at the same wavelength and the same level of data processing sophistication. To the extent that the data processor works with higher quality data, i.e., data having a higher signal to noise or signal to clutter ratio, the probability of acquiring, detecting, identifying, and designating an actual target is much greater.
Smart weapons systems heretofore known have been plagued with the problem of small sensor aperture and relatively poor quality target identification data because of the limitations on the aperture size of the sensors included in each munition or submissile. This has also limited the bad weather capabilities of the prior art systems because rain, fog, etc., further degrade the resolution with which small aperture sensors can scan a target area.
Smart weapons systems have also proven to be extremely expensive due partially to the requirement that a significant amount of advanced technology must be fabricated in a small package in order to fit the data processor, sensor, submissile guidance circuitry, and munitions into the small volume available in each submissile. This requires a high degree of custom integrated circuitry for performing the data processing requirements at a high rate. The greater the sophistication of such circuitry the more susceptible the system is to breakdown and the higher the system cost.
Another drawback of presently available smart weapons systems arises from the autonomous operation of the submissiles following launch. If a carrier releases a plurality of submissiles in the area of a target, there is no means for preventing each of the submissiles from identifying and selecting the same target, e.g., the target with the strongest signature, while ignoring other targets in the same general area which might have only slightly less prominent signatures. This result wastes the advantage of launching a plurality of submissiles at one time and may nullify the effectiveness of the weapons by leaving the majority of possible targets unscathed.
The net result is that smart weapons systems have heretofore been plagued with problems that have yet to be overcome, including very high cost, inherent unreliability because of high complexity, and prohibitively high developmental costs. Finally, since each individual submissile is smart, the expense of the missile system is greatly exacerbated by the need to duplicate costly sensors and data processor circuitry in each submissile.